The new species Cora sanctae-helenae Lücking and Cora trindadensis Lücking, M. Cáceres, N.G. Silva & R.J.V. Alves are described from the South Atlantic islands of Saint Helena (British Overseas Territory) and Ilha da Trindade (Brazil). Both are putative endemics for each of the two islands. Cora sanctae-helenae is with certainty known from three independent historic collections from Saint Helena; it has not been encountered in a recent survey and may have become extinct, considering the massive transformation of native vegetation on the island to farmland and eroded areas. In contrast, C. trindadensis was encountered during more recent surveys on Ilha da Trindade. In addition, a lectotype is selected for C. gyrolophia Fr., the only species of Cora known from the Paleotropics, based on a single gathering (two collections) from the Mascarenes (Mauritius). Cora trindadensis, C. sanctae-helenae and C. gyrolophia represent the three easternmost and only extra-American occurrences of Cora, which is otherwise an exclusively neotropical to southern South American genus (including the Galápagos Islands and the Juán Fernández Islands). While the geographic origin of the type material of C. gyrolophia was in some doubt, the phylogenetic relationships of the vascular plant flora of Saint Helena indicate partial affinities with the Neotropics and South America on the one hand and with Africa and the Mascarenes on the other, placing the occurrence of Cora in the South Atlantic and the Mascarenes in a new perspective as a possible eastward expansion of the genus originating from South America.